The present invention relates to a tape cassette storage box which stores a tape cassette.
A tape cassette storage box is known which comprises a main body which has a tape cassette detachable opening and an auxiliary opening, the tape cassette detachable opening detachably holding a tape cassette which has two surfaces mutually spaced apart parallel to each other and rotatably holding reel hub and four side surfaces connecting the two surfaces and continuing along rims of the two surfaces, one of the two surfaces being exposed to the outer atmosphere, and the auxiliary opening exposing one of the four side surfaces of the tape cassette held in the main body to the outer atmosphere; a cover which is rotatably mounted on the main body and is rotatable between a first position where the cover covers the tape cassette detachable opening and stores the tape cassette in the main body in cooperation therewith and a second position where the cover is spaced apart from the tape cassette detachable opening to allow mounting/demounting of the tape cassette in and from the main body through the tape cassette detachable opening; and a tongue portion which moves together with the cover, and which covers the auxiliary opening and faces said one of the four side surfaces of the tape cassette which is held in the main body when the cover is located in the first position, and an end portion of which, being away from the cover, comes close to said one of the four side surfaces of the tape cassette which is held in the main body when the cover is moved from the first position to the second position.
In some of the conventional tape cassette storage boxes of this type, a kangaroo pocket is formed at the tongue portion of the tape cassette storage box so as to facilitate mounting/demounting of the tape cassette in and from the main body.
In the conventional tape cassette storage box which has a kangaroo pocket at the tongue portion, the tape cassette must be slid along the inner surface of the cover for easy mounting or removal of the tape cassette in or from the main body. However, when the tape cassette storage box is placed on a flat surface, for example, on the top surface of a table, and when the tape cassette is mounted or demounted in or from the main body by one hand, the sliding operation as described above is difficult to accomplish. This difficulty increases when the size of the tape cassette is made small. For example, the difficulty increases when a microcassette is handled as compared with a compact cassette.
Another tape cassette storage box is proposed in Japanese Utility Model Publication No. 49-26,257.
A main body of this tape cassette storage box has another auxiliary opening which opposes the auxiliary opening as described above. Another side surface which is parallel to said one side surface of the four side surfaces of the tape cassette which is held in the main body is exposed to the outer atmosphere through this additional auxiliary opening. The main body of the tape cassette storage box has rotation preventing members which engage with the reel hubs so as to prevent the rotation of the reel hubs. These rotation preventing members have surfaces which gradually incline toward the cassette detachable opening when viewed from the one auxiliary opening to the other auxiliary opening. The cover has another tongue portion which closes the other auxiliary opening when the cover is located at the first position and which moves away from the tape cassette held in the main body when the cover is located at the second position.
In this conventional tape cassette storage box, when the cover moves from the first position to the second position, the tongue portion comes in contact with one of the four side surfaces of the tape cassette held in the main body. Therefore, the force toward the other auxiliary opening is applied to the tape cassette. The tape cassette which is urged by the tongue portion makes the reel hubs slide along the inclined surfaces of the rotation preventing members. In this manner, the tape cassette moves from the main body through the tape cassette detachable opening to the outer atmosphere.
This conventional tape cassette storage box has several drawbacks. The main cause of these drawbacks is that the reel hubs and the rotation preventing members are in slidable contact with each other when the tape cassette is mounted or demounted in or from the main body. In particular, when the frictional force between the reel hubs and the rotation preventing members is suddenly increased for some reason, a relatively large force is applied to the tongue portion, the cover, the pivotal axis of the cover, and the rotation preventing members, resulting in damage to the tongue portion, the cover, and the pivotal axis of the cover.